Mobile anchoring and fall prevention device

ABSTRACT

This device makes it possible to ensure the security of workers of any trade who operate from the inside of a building, on a wall, through a bay in the wall, while in the vicinity of empty spaces and without damaging the inner or outer existing structures (floor, wall, ceiling), characterized in that it comprises: 
     According to the invention, the device comprises:
         a rigid structure ( 7, 10, 12 ) to be placed opposite the bay;   two arms ( 15 ) connected to the upper part of the structure ( 7, 10, 12 ), intended to bear on the wall, above the bay and on either side thereof, and   an anchoring point ( 16 ) integral with the structure ( 7, 10, 12 ), located at the upper portion thereof.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of International ApplicationPCT/FR07/02108 (U.S. National Phase Ser. No. 12/520,422) of XavierJULLIARD filed 19 Dec. 2007 for MOBILE ANCHORING AND FALL PREVENTIONDEVICE, the contents of which are herein incorporated by reference.Application PCT/FR07/02108 claims foreign priority to Application FR0611172 filed 21 Dec. 2006, the contents of which is hereby incorporatedby reference.

TECHNICAL FIELD

The present invention concerns a method and a device for temporary andtransportable anchoring, making it possible to attach personalprotective equipment (PPE), fall prevention safety system.

The present invention also concerns a device for securing work in frontof a door, balcony or window ledge due to the height at which it islocated above the ground.

BACKGROUND OF THE INVENTION

Work on window ledges, balcony ledges or other work at heights near theoutside poses serious safety problems given the risks of operatorsfalling. These risks are particularly present due to the height at whichthe openings are found above the ground.

These risks are also present when it is impossible to use a platformfrom the outside, or a work structure such as scaffolding.

As fixed anchoring element, we know structural anchors making itpossible to connect fall prevention personal protective equipment. Werecall that a structural anchor is an element durably fixed on astructure to which it is possible to attach PPE. Their placement takes along time and they require a waiting time before use if chemical sealingis used, in addition to causing damage to the facades.

As mobile anchoring element, we also know an aluminum ring requiring twofastenings by penetrating a wall near the worksite. One recalls that ananchoring point is an element to which personal protective equipment canbe attached after installation of the anchoring device. This anchoringpoint is generally a ring or any other means resistant enough to absorbthe fall of an operator connected thereto via PPE. They cause damage andrequire a long time to place.

As mobile anchoring element, we also know a door or window bar. It isplaced through a door or a window opposite the direction of the fallrisk. A ring at the center of the bar enables hooking of PPE connectedto the operator. It can be used by one or two people depending on thewidth of the door. In case of operator fall, the bar stops the fall. Itsdrawbacks are that: the mooring is lower than the operator, whichresults in reducing, in case of fall, the stress exerted on the rope andthe mooring; the rope goes through the entire site, even the ground,causing a bother for the operator; the door is not always facing theworksite, which makes its use impossible in many scenarios.

Fatal accidents occur because all currently known devices on the workmarket have serious drawbacks in terms of placement, complexity,installation cost, installation time, specific adaptation to certainworksites for which they do not work; in addition, most of these devicesindeed require alterations such as boring into walls making it possibleto secure an anchoring, which the owners of the sites refuse.

The operators' security is not always ensured when the duration of thework at a height is short-lasting, or if the work takes less time thanthe placement of the security devices existing today. They opt for thefall risk rather than for safety.

In summary, the known devices are so unsuited, long to implement,restrictive, or damaging for the sites that the workers working atheights do not use any security measures, thereby taking the risk of afall.

Documents AE-387 143 and DE 93 18 317 also describe devices which can beused in this application but are not satisfactory.

SUMMARY OF THE INVENTION

The present invention aims to resolve all of the drawbacks of theexisting devices.

The mobile anchoring and fall prevention device makes it possible toensure the security of workers of any trade who operate from the insideof a building, on a wall, through a bay in the wall, while in thevicinity of empty spaces and without damaging the inner or outerexisting structures (floor, wall, ceiling).

According to the invention, this device comprises:

a post comprising a first elongated member and a second elongatedmember, one of these elongated members being telescopically engaged inthe other elongated member;

a support plate intended to bear against a floor of the building,connected to the end of the first elongated member that is opposite tothe end facing the second elongated member;

first adjusting means, for adjusting the position of the first andsecond elongated members relative to each other;

a mounting part attached to the end of the second elongated memberopposite to that facing the first elongated member, comprising two pairsof walls arranged in planes parallel to the longitudinal direction ofthe second elongated member, laterally projecting of the mounting partand being located at a same height from each other; the walls of a firstof these two pairs of walls are parallel to each other and pierced withholes, forming a first articulation yoke, and the walls of the second ofthese two pairs of walls are also parallel to each other and piercedwith holes, forming a second articulation yoke, the walls of the secondpair being arranged substantially at 90° with respect to the walls ofthe first pair; the mounting part also includes an anchoring ringlocated on the side of the second elongated member on which are locatedthe articulation yokes, and at the same height, or at substantially atthe same height, than the latter;

two arms; one end of a first arm is intended to be fittingly engaged inthe first articulation yoke and one end of the second arm is intended tobe fittingly engaged in the second articulation yoke, each arm beingretained in the corresponding articulation yoke by a pin engagedtherethrough and through the walls of the articulation yoke; the armsare thus able to pivot between a folded position in which they extendalong the first and second elongated members, and an unfolded positionin which these arms extend substantially perpendicular to the first andsecond elongated and substantially perpendicular to each other; each armincludes, at its end opposite to that connected to the correspondingarticulation yoke, a support plate intended to bear against the wall ofthe building comprising the bay;

the first and second elongated members are intended to be positionedwith respect to each other so that, when the post is placed in front ofthe bay and bears on the floor and when the arms are in the unfoldedposition, the support plates of the arms bear against the wall of thebuilding, up to the top of the bay or above the bay and on both sides ofthe bay, the anchoring ring being thus also located at the top of thebay or above the bay.

The device according to the invention makes it possible to resolve thedrawbacks of the existing devices, in that it operates perfectly in allscenarios and is quickly installed. It is usable immediately after itsinstallation. It is installed in less than two minutes and enables allwork which has a fall risk for the operator without it. It isparticularly adapted to be able to perform all types of work at heightsabove the ground:

inside a building,

outside a building,

upright on a window ledge

inside a site, on a stepladder close to an open window.

It makes it possible to avoid using a structural or mobile anchoringrequiring mechanical fixing, using a platform from the outside of thebuilding, a scaffolding, a ladder.

Potentially usable by:

operators repairing defective rolling slat blinds, installing workoutside or near the outside.

window washers,

operators installing equipment on an outer façade,

operators working on a ladder inside or outside, or on a stepladderinside.

all operators having to perform work at a height not allowing theinstallation of structural anchoring points, the use of scaffolding or aplatform. Non-exhaustive list.

The aim of the invention is thus to propose a method and a device fortransportable temporary anchoring, with a particularly simplified andquick, secure, efficient, non-damaging installation for the site whereit is installed, with great freedom of choice of the installation site.

It will be understood that “fittingly engaged” means that the arms canrotate in the articulation yoke but without any transverse play, sothat, when they are in the unfolded position and bear against the wallof the building comprising the bay, they can not substantially move awayfrom one another and provide a stable support to the device.

Preferably,

the mounting part is hollow and internally forms a conduit communicatingwith a conduit formed in the second elongated member, the conduitsallowing the engagement in them of a third telescopic elongated member,this third elongated member comprising a support plate at its endopposite to that engaged in the conduits, intended to bear against aceiling which the building includes;

the device comprises second adjusting means, for adjusting the positionof the third elongated member relative to the second elongated member.

This third elongated member and the support plate connected theretoallow the device to bear against the ceiling of the building.

The first and/or second adjusting means comprise:

a system of holes provided in the first and second elongated membersand/or the second and third elongated members, and at least one key.

The device further comprises advantageously:

means for making fine adjustments to the length of the post, with thepossibility of tightening, acting at the level of at least one end ofthis post, these adjustment means making it possible to achieve tightapplication of the support plates of the post against the floor and theceiling, respectively.

Advantageously, the device comprises:

at least one slider engaged on the second elongated member with thepossibility of sliding;

two spacers each of which is pivotally connected to one of the arms andto the slider, and

a part secured on the second elongated member, forming a stop againstwhich the slider abuts in the deployed position of the arm.

According to another aspect of the invention, the two arms are, on theside opposite the post, connected to each other by a cable, which limitsany possibility of separation of one arm in relation to the other.

This cable can, at its central part, be connected to an elastictightener facilitating folding of this cable during folding of the armsin relation to the post.

The device can comprise rigid elements able to bear on the edgesdefining the bay, in particular deployable inside the bay, theadditional structure formed by these rigid elements being connected tothe structure of the device. Additional stabilization of the device isthus realized and lifting of loads through the bay can be done.

The additional structure can comprise at least one bar designed to bearon one of the edges defining the bay and preferably at least two bars,at least one of which is designed to bear against a lower edge definingthe bay and the other of which is designed to bear against an upper edgedefining the bay. At least one of the bars of the additional structureis advantageously adjustable in length.

The device can also comprise a console including a floor and a railingdesigned to be placed on the outside the bay, this console beingconnected to the rest of the device by at least one arm and/or at leastone cable.

When the first adjusting means comprise at least two telescopicelements, the device advantageously comprises:

a lower base on which is mounted the first elongated element, with thepossibility of sliding in relation to this base,

a spring inserted between this base and this first elongated element,

a pedal mounted pivoting on the base, and

a rod connecting the pedal and the first elongated element.

Actuating the pedal thus makes it possible, via the rod, to cause thetelescopic element to slide vertically against the elastic force of thespring to enable easy returning of this telescopic element to adetermined sliding position in relation to the adjacent telescopicelement. This determined sliding position can in particular be that inwhich the holes comprised by one of the telescopic elements are oppositethe holes comprised by the other telescopic element, so as to make itpossible to facilitate the insertion through these respective holes of apin for immobilizing one telescopic element in relation to the other.

Description:

Light structure, assemblable and disassemblable made in aluminum orsteel, with circular, square, rectangular or other section, which ismade up of three or four elements depending on the height under theceiling of the worksite.

It is a structure bearing on four points: one on the floor, two againstthe wall and a fourth point vertically opposite the point on the flooragainst the ceiling, this last point not being essential.

the first bearing point, on the floor, very pulled back in relation tothe inner wall, leaves a usable work space for placement of carpentry,installation of a stepladder, scaffolding, . . . of the materialnecessary for the worksite.

the two bearing points against the wall are positioned on either side ofthe bay at eye level, close to the ceiling.

a vertical blocking system immobilizes the system.

Operation and Placement:

BRIEF DESCRIPTION OF THE DRAWINGS

The appended drawings illustrate the invention:

FIG. 1: complete perspective view of the device according to theinvention.

FIG. 2: side view of the lower portion of the device according to theinvention.

FIG. 3: side view of the upper portion of the device according to theinvention.

FIG. 4: side view of the raising part of the device according to theinvention.

FIG. 5: top view of the device according to the invention without theraising part.

FIG. 6: complete side view of the device according to the invention.

FIG. 7: side view of the extension of the device according to theinvention.

FIG. 8: side view of the upper portion folded.

FIG. 9: perspective view of the device according to the inventionprovided with options.

FIG. 10: side view of a variation of embodiment of an additionalstructure which the device may comprise.

FIG. 11: perspective view of a console which the device may comprise.

FIG. 12: variation of embodiment of a base which the device comprises.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a perspective view of the device according to the invention,from the inside of a building.

FIG. 2 is a side view of the lower portion of the device according tothe invention. It is provided with a base (1) providing a supportsurface making it possible to distribute the load. Placed on the floorof the building, this base allows stability of the device during itsassembly. The underside of this base may be provided with a small foammat with a small thickness (2) able to prevent damaging the floors. Onthis base is secured a plate (3) on which a device is maintainedallowing blocking and slight vertical pressuring of any structure fromthe top and from the bottom once the set of assembly operations aredone. This vertical blocking can be done using a system such as a gascylinder or any other system, in this case in FIG. 1 a mechanical systemwith reversed threadings of the turnbuckle type (4). A threaded rod (5),lower portion of the tightener is secured on the plate (3). A secondthreaded rod (6) making up the upper portion of the turnbuckle issecured at the end of a bar (7) forming a first elongated member. In theupper portion of the bar (7), a hole (8) allows placement of a key (9).

FIG. 3 is a side view of the upper portion of the device according tothe invention. It fits into the lower portion by sliding of the bar(10), forming a second elongated member, inside the bar (7).

At the top of the bar (10), a hollow mounting part (11) is securedinside which the bar (12) shown on FIG. 4, forming a third elongatedmember can move vertically, the latter part being immobilized using theblocking key (13) housed in the hole (14) located on top of the part(11).

The mounting piece (11) is fixed on the end of the second elongatemember (10) opposite to that facing the first elongate member (7). Itcomprises two pairs of walls arranged in planes parallel to thelongitudinal direction of the second elongate member (10), these wallsprojecting laterally of the mounting piece (11) and being located at thesame height to one of the other; the walls of a first of these two pairsof walls are parallel to each other and pierced with holes, forming afirst articulation yoke, and the walls of the second of these two pairsof walls are also parallel to each other and pierced with holes, forminga second articulation yoke. As shown particularly in FIG. 5, the wallsof the second pair are disposed at substantially 90° of the walls of thefirst pair.

The mounting piece (11) also comprises an anchoring ring (16) located onthe side of the second elongate member (10) on which are the drawbararticulation, and at the same height, or substantially at the sameheight, as these. This anchoring ring (16) FIGS. 1, 3 and 6 allows theattachment of the user's PPE.

The device also comprises two arms (15); one end of a first arm (15) isdesigned to be engaged so adjusted in the first cover and a hinge end ofthe second arm (15) is intended to be engaged fitting manner in thesecond joint yoke, each arm (15) being retained in the yoke by acorresponding pin (17) therethrough and through the walls of the fork.The arms (15) and are pivotable between a folded position (see FIG. 8),in which they extend along the first and second elongate members (7,10), and an unfurled position (see FIGS. 1, 3, 5), wherein the arms (15)extend substantially perpendicular to the first and second elongatedmembers (7, 10) and substantially perpendicular to each other, each arm(15) comprises, at its opposite end to that connected to thecorresponding articulation yoke, a bearing plate (23, 24) intended tobear against the building wall comprising the bay. On this hollow part(11) between the two arms (15) is the anchoring ring (16) FIGS. 1, 3 and6 allowing hooking of the operator's PPE. The two arms (15) arearticulated at one of their ends in (17) on the part (11) and severaltens of centimeters from this articulation in (18), a bar forming aspacer (19) is articulated in (18) on the arm (15) and in (20) on thesliding hollow part (21).

These two arms (15) are articulated at one of their end (17) on the part(11) and a few tens of centimeters of this articulation in (18), a bar(19) forming a spacer being articulated at (18) on the arm (15) and in(20) on the hollow sliding part (21).

The hollow part (21) allows, by its upward vertical movement along thebar (10) thereby abutting against the hollow part (11), the deploymentof the two arms (15).

As can be seen with reference to FIGS. 1 and 5, the first and secondelongated members (7, 10) are intended to be positioned with respect toeach other so that, when the amount is placed that they form in front ofthe bay bearing against the floor by the plate (1), and that the arms(15) are unfolded position, the bearing plates (23, 24) of the arms (15)bear against the building wall comprising the bay, up to the top of thebay or the bay above and on both sides of the bay. The anchoring ring(16) and is also located at the top of the bay or the bay above.

These two arms (15) are thus spaced apart from each other, in this caseperpendicular to each other. They are provided, at their other end, witharticulations (22). These articulations receive “load distributing” pads(23) equipped with protective foam (24) bearing on either side of theopening on the inner wall of the worksite. The articulations (22) allowcontact against a wall, regardless of its state and the folding of thedevice.

These two arms (15) are connected to each other by a cable (25) FIG. 5by two rings (26).

An elastic tightener (27) FIG. 5 connects the middle of the cable (25)at the top of the part (11) FIGS. 3 and 5 to a ring (29) facilitatingbending of the cable during closing of the structure.

The spacers (19) FIG. 3 articulated in two points (18) and (20) helpopening and closing, by means of the handle (28) secured on the hollowpart (21).

The blocking key (30) housed in the hole (31) locks the element (21) inthe high position, thereby keeping both arms (15) supported by the arms(19) in the open position.

FIG. 4 is the side view of the element making it possible to raise thedevice according to the invention. Adjustment of its height is done bysliding its lower bar (12) inside the bar (10) and immobilizing it usingone of the bores (32), located on the bar (12). This raising part isblocked by using the key (13) housed in the hole (14). This raising partis provided on top of a plate (33) able to be articulated, on which issecured a load distributing pad (34) equipped with foam (35), in orderto avoid destroying the ceiling. This upper element FIG. 3 slidesvertically via the bar (10) in the bar (7) until the foam (35) comesinto contact with the ceiling. It is immobilized as close as possiblethereto via a second blocking key (9) which is housed in the hole (8) onthis bar (7) and in the closest hole available on the bar (10). Thevertical blocking immobilizing the structure is done via the turnbuckle(4).

The anchoring ring (16) located on top FIGS. 1, 3, 5, 6:

prevents the rope from dragging on the ground, decreasing the risk ofdamage thereof.

decreases, due to its position, the shock force absorbed by theanchoring and the fall factor, which thus cannot be greater than 1. Onerecalls that the shock force is much greater than the body weight. Itcan cause the breakage of the rope, cable or mooring or hurt theindividual. There is a shock when the rope blocks the operator. Itsvalue depends on the height of the fall. The fall factor is equal to theheight of the fall divided by the length of rope used. This must be aslow as possible.

This anchoring point allows the operator to be connected to thestructure via his PPE before mounting the stepladder and to obtainsupport on the edge of the window or another high up opening.

For sites equipped with suspended ceilings, the raising part integratedinto the upper element FIG. 2 slides vertically until it reaches theexisting ceiling. Blocking by captive key (13) FIG. 3 equips thisraising part, which allows plenums of large heights.

For sites with under-ceiling heights greater than three meters: anextender FIG. 7 made up of two coupled arms (36) and (37) fitting intothe arms (7) and (10), respectively, makes it possible to raise theentire structure. An additional blocking key (38) allows itsimmobilization.

The structure FIG. 3, once folded FIG. 8, fits into an areacorresponding to the lower and upper plates. It is stored in a bagprovided with handles and/or straps allowing it to be transported as abackpack. It is easily transportable on the worksite thanks to its smallweight.

The dimensions can be modified (decreased or increased) to meet theneeds of less common scenarios.

The bulk of this structure can be reduced by half in terms of heightonce folded if it is made with arms (15) FIG. 8 and arms (10) FIG. 8 (7)FIG. 2 (37) FIG. 7 coupled to each other.

This structure can be provided with additional support points on thefloor to increase its stability during assembly and disassembly.

A possible copy would consist of replacing the vertical blockage(turnbuckle), and the support point at the ceiling, by an additional setof legs and crosspieces limiting the interest of the system butnevertheless procuring the same advantages as the structure presentedabove. This structure would then be stable in itself, longer toimplement, certainly more heavy and bulky but nevertheless can be higherperformance because it does not require the presence of a supportsurface on top.

Another use of this device would consist, in other scenarios, of liftingloads from the street to the floor concerned by the work FIG. 9. Byusing a bar 39 connected from one side on top of the structure to theroom (11) and at the other end with two arms (40) and (41) resting intwo points on the edge of the window or the opening. These three armsare connected to each other by a connecting portion comprising, in itslower face, a lifting ring on which a return pulley could be installed.This pulley could be used as angle return. It could also be used toavoid friction of the wire used for insurance for an operator workingdown below the façade outside the building. All of this new structureFIG. 9 together with a hoist could be used as means for lifting loadsfrom the ground.

FIG. 10 shows that the bar 39 can be a telescopic structure in order tobe adjustable in length, and that the additional lifting structureformed by the bars 39 to 41 can be completed by an additional upper bar42, connected to the part which makes it possible to assemble the bars39 to 41 to each other and bearing on the edge of the wall of thebuilding defining the bay in the upper portion. This bar 42 can have atelescopic structure in order to be adjustable in length and to beequipped with a tightener 43. The part which makes it possible toassemble the bars 39 to 42 to each other can comprise a pulley on whichthe lifting cable passes.

FIG. 11 shows that the device can also comprise a console 45 including afloor and railing, designed to be placed on the outside of the bay, thisconsole 45 being connected to the device by at least one cable 46. Atool fall prevention net 47 can be stretched between the bay and theconsole 45.

FIG. 12 shows a variation of embodiment of the lower base 1. This base 1comprises a vertical finger on which the telescopic element 7 is mountedwith the possibility of vertical sliding in relation to this base. Aspring 50 is engaged on the vertical finger while being inserted betweenthe base 1 and the telescopic element 7. A pedal 51 is mounted pivotingon the base 1, and a rod 52 connects the pedal 51 and the telescopicelement 7.

Actuation on the pedal 51 makes it possible, via the rod 52, to causethe telescopic element 7 to slide vertically against the elastic forceof the spring 50 to make it possible to easily bring the telescopicelement 7 into a determined sliding position in relation to the adjacenttelescopic element 10. This determined sliding position can inparticular be that in which the holes comprised by one of the telescopicelements 7 come across from the holes comprised by the other telescopicelement 10, in order to make it possible to facilitate the insertionthrough these respective holes of an immobilization pin 9 of onetelescopic element 7 in relation to the other.

1) A mobile anchoring and fall prevention device to ensure the securityof workers who operate from the inside of a building, on a wall, througha bay in the wall, while in the vicinity of empty spaces and withoutdamaging an inner or an outer existing structures comprising: a postcomprising a first elongated member and a second elongated member, oneof these elongated members being telescopically engaged in the otherelongated member; a support plate adapted to bear against a floor of thebuilding, the support plate connected to the end of the first elongatedmember that is opposite to the end facing the second elongated member; afirst adjusting device, for adjusting the position of the first andsecond elongated members relative to each other; a mounting partattached to the end of the second elongated member opposite to thatfacing the first elongated member, the mounting part comprising twopairs of walls arranged in planes parallel to the longitudinal directionof the second elongated member, laterally projecting of the mountingpart and being located at a same height from each other; the walls of afirst of these two pairs of walls are parallel to each other and piercedwith holes, forming a first articulation yoke, and the walls of thesecond of these two pairs of walls are also parallel to each other andpierced with holes, forming a second articulation yoke, the walls of thesecond pair being arranged at 90° with respect to the walls of the firstpair; the mounting part includes an anchoring ring located on the sideof the second elongated member on which are located the articulationyokes, and at the same height, or at the same height, than the latter;two arms; one end of a first arm is intended to be fittingly engaged inthe first articulation yoke and one end of the second arm is intended tobe fittingly engaged in the second articulation yoke, each arm beingretained in the corresponding articulation yoke by a pin engagedtherethrough and through the walls of the articulation yoke; the arms topivot between a folded position in which they extend along the first andsecond elongated members, and an unfolded position in which these armsextend perpendicular to the first and second elongated and perpendicularto each other; each arm includes, at its end opposite to that connectedto the corresponding articulation yoke, a support plate adapted to bearagainst the wall of the building comprising the bay; the first andsecond elongated members are adapted to be positioned with respect toeach other so that, when the post is placed in front of the bay andbears on the floor and when the arms are in the unfolded position, thesupport plates of the arms bear against the wall of the building, up tothe top of the bay or above the bay and on both sides of the bay, theanchoring ring being located at the top of the bay or above the bay. 2)The device according to claim 1, wherein: the mounting part is hollowand internally forms a conduit communicating with a conduit formed inthe second elongated member, the conduits allowing the engagement inthem of a third telescopic elongated member, the third elongated membercomprising a support plate at its end opposite to that engaged in theconduits, adapted to bear against a ceiling which the building includes;and the device comprises a second adjusting device, for adjusting theposition of the third elongated member relative to the second elongatedmember. 3) The device according to claim 1, wherein the first and/or thesecond adjusting device comprise a system of holes provided in the firstand the second elongated members and/or the second and third elongatedmembers, and at least one key. 4) The device according to claim 2,further comprising: a device for making fine adjustments to the lengthof the post, optionally tightening, acting at the level of at least oneend of the post, the adjustment device tight the support plates of thepost against the floor and the ceiling, respectively. 5) The deviceaccording to claim 1, further comprising: at least one slider engaged onthe second elongated member with the possibility of sliding; two spacerseach of which is pivotally connected to one of the arms and to theslider, and a part secured on the second elongated member, forming astop against which the slider abuts in the deployed position of the arm.6) The device according to claim 1, wherein the two arms are, on theside opposite the post, connected to each other by a cable, which limitsany possibility of separation of one arm in relation to the other. 7)The device according to claim 6, wherein the cable is connected at acentral part to an elastic tightener facilitating folding of the arms inrelation to the post. 8) The device according to claim 1, furthercomprising: a lower base on which is mounted the first elongatedelement, with the possibility of sliding in relation to this base, aspring inserted between this base and this first elongated element, apedal mounted pivoting on the base, and a rod connecting the pedal andthe first elongated element.